Switch mechanism



Patented Dec. 13, 1927.

UNITED FLOYD B. KNISKERN AND JAMES R. SLLUSTER, 0F WXLKNSBURG, PENNSYLVANIA, AS-

SIG'NORS TGr WESTINGHOUSE ELEGTR-() AND IVEANUFACTURING COMPANY, A COR- PORATION OF PENNSYLVANIA..

SWITCH i/IECHANISM.

Application filed March 24, 1921. Serial No. 455,218.

Our invention relates to switch mechanism and particularly to enclosed switch mechanism of the safety type. t

One object of our invention is to provide an enclosed switch mechanism wherein separate covers are provided for preventing)l access to the switch elements and to the 'ruse elements and wherein both. covers are' so interloclred with the switch that they are locked in closed position so long as the switch is in closed position.

Another object of Our invention is to pro-` vide a switch mechanisnrI having the above characteristics, wherein the switch is held in open position so long as the cover is in open position.

Aiurther object oi our invention is to provide a switch mechanism ot the enclosed type wherein the terminals are connected to the switch mechanism by means ot a detachable plug or connector and wherein the connector is so interlocked with the switch mechanism that it cannot be disconnected therefromso long as the switch is in closed position, and wherein means are provided :tor preventing the attachment oi the plug` while the switch is in Closed position.

Another 'object of the invention. is to provide a housing 'for a switch mechanism for heavy currents and which may be constructed ot' cast metal and which is substantial in every detail, weather prooi and practical for application in mines, on portable apparatus and other installations in which the apparatus will be subjected to rough usage and 'to operation by uneXpei-ienced attendants.

These and other objects, that will he made apparent throughout the further description of the invention, are attained by means ot the switch mechanism hereina'iter described and illustra-ted in the accompanying drawings, wherein:

Figure l is a front view ot the switch mechanism;

Fig. Q is an elevational view ci one of the mechanism shown in Fig. il;

'y Fig. 3 is a sectional view oi a 'fragment ot the apparatus, taken on the line ill-Eloi Fig. looking in the direction ott the arrows; and Y Fig. l is a sectional view oi a fragment ot side switch-blade members 2l.

a switch mechanism to be hereinafter described and' is provided with a. cover 9 which is hinged to a side of the housing 5 by means of the hinge ll.. rlvhis cover is provided with slotted lugs l2 that are disposed on opposite sides of the cover and are adapted to receive the free ends .of eye bolts 13 that are pivoted, by means ot rivets 14. to integral lugs 15 on the sides ot the housing The lid is clamped in closed position yby means of wing nuts i6 mounted on the threaded ends of the eye bolts 13.

The section 7 contains iiuse mechanism to be hereinafter described and is provided with a cover 'i7 that is hinged to one end ot the housing 5 by means of a hinge i8. This cover is provided with lugs l2, similar in every respect to those on the cover 9, and is clamped to the housing by eye bolts 1B in a manner similar to that in which the cover 9 is clamped.

An insulating panel 'i8 is secured to the bottom of Jthe housing upon which vthe switch and fuse mechanism .is mounted. The switch mechanism is o'l" the three-pole type tor use in a three-wire system and includes three switch-j aw members i9 to which switchblade members 2l are pivotally attached. Three rswitch-jaw members 9.2 are disposed upon the panel and opposite the pi vot-jaw members i9 and are adapted to receive the The line terminals 28 are connected to the switch-jaw members 9.2.

The portion oi? the paneldisposed beneath the cover l? is provided with three pairs of the housing 5 and is adapted to receive a connector plug 3l to which the flexible cable 32, containing the load conductors is attaehed.

The line terminals from the cable conduit terminate in a connection box 33 that is detachably secured to the housing 5 by means of bolts 34. It will be seen from the toregoing` that the circuit through the box is from the line terminals 23 through the switch-blade members 2l, the fusemembers 25 and the load terminals 27, and that, when the switch members 2l are in open position, the fuses 25 are disconnected trom the eircuitand may be inspected or changed without danger or injury.

In order to insure that the fuses shall be .inaccessible while the switch is in closed position, interlocking means, to be hereinafter described, is provided between the switch and the covers closing the housing. As this switch mechanism is particularly adapted for use in circuits carrying heavy currents, and as, in mine work, where circuit-opening contacts should be totally enclosed to prevent explosion ot mine gases, it is desirable, as a matter ot absolute protection, that the connector plug C151 may not be disconnected from the receptacle 29 so long as current is passing through the circuit, Interlocking means is, therefore, provided between the switch and the connector plug whereby the plug is retained in operative current-conducting engagement with the receptacle so long as the switch remains in closed position. Asa :further precaution, the interlocking means is made of such a nature that the plug- 3l cannot be attached to the receptacle for the purpose ot completing the circuit unless the switch is in open position.

The interlocking mechanism for the cover closing the switch compartment, the cover for closing the fuse compartment and the connector plug will be described in the order named. The switch-blade members 21 are connected at their free ends, by means of an insulating bar 35, and the switch is operated by means of an operating lever 36 that is pivoted to the side of the housing 5 within a bearing 37. The operating lever 36 is provided with two extensions 88 that operatively engage the insulating bar The lever 3G is also provided with an operatingr shaft 39 which extends through the bearing 37 and is provided with an operating handle 4l by means of which the switch lever 36 may be turned in order to move the switch-blade members to open and to closed positions.

The lever 36 is provided adjacent the shaft 39 with an arcuate cam 42, (see Figs. 2 and 3), the inner surface 43 of which is concentric to the axis of rotation of the lever or to the center of the shaft 39. The tree end ot the cover 9 is provided with an integral inwardly projecting lug 44 that provided, at one corner of its extremity, with a cylindrical. boss or projection 45 which engages the inner surface et the cam 42 when the switch lever EG is in closed position.

Opening movement ot the cover 9 is prevented by the engagement of the boss i3 with the cam. lVhen the lever 36 is moved to open position, the cani 42 so moved that the end thereof clears the boss 45 and permits the cover to be moved to open position. It will be seen from the foregoing that, so long the switch is in closed position, the cover cannot be opened.

In order to prevent the closing` ot the switch while the cover is open, an interlocking means is provided which consifils of a floating plate 47 that is provided with two fixed rods 48 and 49 which extend outwardly from the plate 47. A. stationary rofl 5l is riveted, at its inner end, lo the bottoni ot the housing 5 and serves as a centering guide tor the movement ot the floating plate 47. rlhe rods 49 and 4S prevent rotation ot' the plate about the rod 5l.

Theuppei.' end oit the rod 5l is supported in a bracket'?l cast integral with the side ot the hoiiising This bracket is provided with a perforation 53 through which 'the rod 49 extends and with a perforation 54 through which the rod 48 projects. 'l`he lever 36, adjacent the shaft 39, is provided with an opening 55 which is adapted t register with the opening 5? in the. bracket, when the operating lever 36 is in open position. i

A spring- 5G, that is disposed between the bottom ot' the housing and the tloating plate 47, forces the plate 47 outwardly to more the rod 49 into the opening 55 and thereby prevent rotary movement ot the operating lever 36. Outward movement of the :tloating plate 47 is only possible when the cover 9 is open, for the reason that the lug 44 engages the upper end of the rod 48 ,and depresses the plate 47. When the cover 9 is open, the plate 47 is free to move outwardly and will do so when the opening 55 regisH ters with the opening 52. The lever 36 is then locked in open position and cannot be moved until the cover 9 is moved such distance that the lug` 44 may engage the rod 48 and move the rod 49 out of the opening 55 in the lever 36. It will be evident from the foregoing that the final closing movement of the cover releases the operating lever so that it may be turned to closed position.

The interlocking means for the cover 17 comprises a bellecrank lever 57 that is pivoted to the end et the housing 5 by means of a bolt 58 in such a manner that it turns about an axis perpendicular to the base of the housing. 'The lever is provided with an arm 59 that is disposed across the path ot' movelUU ment of the lug 61 that is a continuation ot a portion of the cover hinge. The lever 57 is pivotally connected to the operating handle 41 by means of a connecting rod 62.

When the switch is moved to open position, the bell-crank lever 51 is rotated to move the arm 59 out of the path ol movement ot the lug 61. The cover 17 may, at this time, be opened. It will be seen from the foregoing that the cover cannot be opened so long as the switch is in closed position.

Vhen the cover 17 is open, the lug 61 rotates about the hinge 18 in such a manner as to prevent the arm 59 from rotating to closed position, thus preventing closing ot the handle 41 until after the fuse compartment door 17 has been closed.

In order to prevent the attachment or detachment of the plug connector 31 when the e switch is in closed position.l a yoke 63, which straddles the conductor 31 and operates in an annular groove 64.- thereot, is mounted for reciprocation on the bracket 65 that is an integral part of the housing. The outer end of the yoke 63 is pivotally connected to the arm 66 of the bellcrank lever 57 and is withdrawn thereby a sufiicient distance to clear the plug connector 31 when the switch handle 41 has been moved to open position. arm 66 is provided with a slot 67 in which the pivot pin 68 operates. It will be seen from the foregoing that, when the switch is in closed position, the plug connector cannot be attached, or, if it is attached, it cannot be disengaged.

While we have described the housing structure as being made of cast metal, it is obvious that the housing may be constructed ot sheet metal and that the various brackets and projecting portions thereof may be separate from the main body of the housing and se- The cured thereto by any desired fastening means. Constructed as illustrated and described, the mechanism is rigid and is positive in its action.

While we have described and illustrated but one embodiment of our invention, it will be apparent to those skilled in the art that various changes, modications, substitutions, additions and omissions may be made in the apparatus illustrated without departing Jfrom the spirit and scope ot the invention, as set forth in the appended claims.

7e claim as our invention:

1. Switch mechanism comprisinga housin g having a switch member within the housing, a fuse member within the housing, separate covers for closing access to the switch member and to the fuse member, a connector tor operatively connecting a conductor to the said members, means for operating the switch member and means actuated thereby Jfor locking the cover members in closed position and the connector in operative relation to the said members so long as the switch is in closed position.

2. Switch mechanism comprising a housing, a switch member within the housing, a fuse member within the housing, separate covers for closing` access to the switch member and to the fuse member, the said covers being hinged thereto on hinges disposed at right angles to one another, and means interlocking the covers with the switch whereby opening movement ot the covers ispreeluded so long as the switch is in closed position.

In testimony whereof, we have hereunto subscribed our names this 18th day of March, 1921.

FLOYD B. KNISKERN. JAMES R. SHUSTER. 

